Specifications

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Cisco MGX 8850 (PXM45) and MGX 8950 Software Configuration Guide

Release 3, Part Number 78-14788-01 Rev. C0, January 2004

Chapter 1 Preparing for Configuration

Planning for Card and Line Redundancy

• Because the AXSM-1-2488 has only one OC-48 port on its back card, this card cannot be configured

for intracard APS operation (although it can be configured for intercard APS, which is described

later in this chapter).

• The switches at both ends of the APS lines must be configured for APS, and the role of each line

(working or protection) must be the same at both ends of the line.

Planning Redundant AXSM/FRSM-12 Configurations with Standalone Lines

In a redundant AXSM/FRSM-12 configuration, matched sets of front and back cards are installed in the

switch, and redundancy is established during software configuration. In a redundant AXSM/FRSM-12

configuration, a failure on the active AXSM/FRSM-12 causes a switchover to the standby

AXSM/FRSM-12 card set, and no calls are lost.

Note This configuration provides fault tolerance for the AXSM/FRSM-12 front card only. This configuration

does not provide fault tolerance for back cards or lines. If you need such a level of protection, use the

redundant AXSM/FRSM-12 configuration with redundant lines.

Figure 1-9 shows how a redundant AXSM/FRSM-12 cards connect to standalone lines.

Figure 1-9 Redundant AXSM Configuration with Standalone Lines

Figure 1-9 shows two complete sets of AXSM/FRSM-12 cards. Each port in an active card slot is

connected to the corresponding port in the standby card slot through a Y-cable, which joins the two ports

to a common line. If the front card in the active card set fails, the standby card set becomes active and

continues to support calls over the shared communication line.

When planning a redundant AXSM/FRSM-12 configuration with a standalone line, consider the

following:

• The redundant AXSM/FRSM-12 cards can be placed in any available slots; they do not have to be

installed in adjacent slots, although doing so makes the cabling easier.

• The AXSM card sets must be identical. You cannot pair nonmatching cards, such as an AXSM

T3/E3 card, with an AXSM OC-3 card.

AXSM front cards AXSM back cards Y-cables

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Midplane